The invention relates to packaging and shipping systems and in particular to packaging of materials and items to be secured as a unit load or to be secured to a shipping and transporting means, such as a pallet. Specifically, it relates to such systems using plastics stretch film (a high cling film) as the binding and securing agent.
A need has existed for some time for a simple and economical means for manually applying plastics stretch film material. This invention provides that simple and economical means to do the work.
In the prior art two methods are available for applying the plastics stretch film material to materials and units to be packaged or secured as hereinbefore described.
One method is to use a very expensive automatic machine to hold a supply of the plastics stretch film and to automatically wrap it around the unit of materials to be packaged; and to secure the unit of materials to a shipping or transporting means. Such machines require the attention of an operator and they do have their own limitations.
Another method is to use a commercial manually operated grabbing or holding device. However, this manually operated device is very expensive in comparison to the cost of the present invention. The commercial device is difficult to adjust to obtain the wide range of speeds and tensions that are required while manually wrapping the plastics stretch film to a unit load. The adjusting system on the commercial unit is such that it is difficult to "feel" the fine line between "full stop" and "just barely moving." As a result, many broken films are encountered during use of the commercial unit. The present invention eliminates these problems and is extremely simple to operate.
One of the devices in the prior art consists of a shaft means passing through the tubular core of the roll of plastics film material. The shaft has more or less "D" shaped hand grips on each end that are held by the operator and used to pull the plastics film around or over the unit or load being packaged or secured. When more tension is to be placed on the plastics film, one of the two hand grips is twisted to tighten the shaft movement through the core of the roll of plastics film. This tightening by twisting one of the hand grips does not provide a sensitive "feel" in the operator's hands and is the cause of the frequent breaking of the plastics film mentioned hereinbefore.
Another of the devices in the prior art consists of a shaft means passing through the aforementioned tubular core of the roll of plastics film material. The shaft also has more or less "D" shaped hand grips on each end as hereinbefore described, but the tension adjustment is provided by a brake-nut on the end of the shaft. Changes in the need for more or for less tension requires the operator to use one hand to operate the brake-nut while holding the roll of plastics film with the other hand in one of the "D" shaped hand grips. This method of adjusting the tension is an awkward operation to perform. In addition, this method also causes frequent breaks of the plastics film.
In the present invention the control of the amount of tension is by the direct pressure or the squeeze of the operators hands on the flexible tube-like devices around extended ends of the core of the roll of plastics material. Two embodiments are provided for extending the core ends of the roll of the plastics material, however, the tension control means is the same in each case.
In the prior art the fixing of the device to a roll of plastics stretch film required considerable time and effort to insert a shaft through or to drive a toothed or spiked shaft into the ends of the core of the roll of plastics stretch film, and then add hand grips, holding or securing nuts, and other such mechanical operations. In the present invention, the preparation is primarily the slipping of two flexible hand grips on the ends of the core of the roll of plastics stretch film or on simple inserts in the core.
It is, therefore, an object of the invention to provide a system for manually applying plastics stretch film to a unit that is economical to manufacture and simple to operate.
It is another object of the invention to provide a system for manually applying plastics stretch film to a unit that permits the operator to "feel" the movement and tension condition through the hands on the device of the system.
It is yet another object of the invention to provide a system for manually applying plastics stretch film to a unit that consists of two simple flexible hand grips.
It is a further object of the invention to provide a system for manually applying plastics stretch film to a unit that does not require the operator to remove the hands from the device to change the tension setting.
Further objects and advantages of the invention will become apparent in light of the following description of the preferred embodiments.